Notes: Roger Federer after skipping the French Open with a back injury returns to kick off the grasscourt season at Stuttgart…Federer is the lone Top 10er, but a strong field includes a number of floaters…The Top 4 seeds receive opening-round byes…Interesting starters include (1) Federer vs. the American top prospect Fritz, (8) Pouille vs. the Aussie Millman (winner to face the Del Potro vs. Dimitrov victor) and (7) Kohlschreiber vs. the French riser Herbert…

Nishikori is the two-time defending champion, last year beating Andujar in the final…”I am happy to be back in Barcelona. I feel good and hope to win my third consecutive title here,” Nishikori said…Nadal won the title in eight of nine years prior to that…

Pulling from the tournament were Roger Federer (knee surgery) and Janko Tipsarevic…The absent Federer is the two-time defending champ, beating Djokovic in last year’s final…Federer and Djokovic have won the last seven titles between them…Djokovic (2013,’11-09) is the lone former champ in the field.

Federer has won the most singles titles of any player in Doha, and is a perfect 3-0 in finals…Ferrer beat Berdych in last year’s final…Nadal, who is playing doubles with Verdasco, has won the most doubles titles of anyone at the event with four (2005,’09,’11,’15)…Former singles champs in the field are Ferrer (2015), Nadal (2014), and Federer (2011,’06-05).

All of the Top 10 and 15 of the Top 16 players post this coming week for the Paris Masters, the final regular-season tournament on the ATP World Tour. Who will be hot going into the ATP Finals, where the Top 8 field is already set?